Abstract:
:A physiological controller is a key component to optimize the performance of left ventricular assist devices (LVADs) from short term to long term (10-20 years). The difficulties of its design lie in the inaccurate modeling of any particular human cardiovascular system because of limited knowledge, the large fluctuation of systemic parameters in normal daily life, nonlinearity introduced by one-way heart valves, and restriction on available sensors. The desired physiological controller for a permanent LVAD is expected to handle different activity levels such as sleeping, resting and exercising, and different pathological levels of left ventricular failure. In this study, a physiological controller designed for a long-term continuous flow (CF) LVAD was tested in a mock circulatory loop. The pressure head across the LVAD and motor signals were used as feedback signals, which were obtained from long-term reliable sensors. Three activities and five different pathological levels of left ventricular failure were simulated to test the performance of the designed controller. The experimental results showed that the designed controller restored the total peripheral flow and arterial pressure, and decreased the left ventricular end-diastolic pressure to a safe range. The suction of the left ventricle was successfully reversed by the designed controller. The controller thus was proven to be able to control the LVAD properly in many of the possible physiological conditions experienced by LVAD recipients in long term.
journal_name
Artif Organsjournal_title
Artificial organsauthors
Wu Y,Allaire PE,Tao G,Adams M,Liu Y,Wood H,Olsen DBdoi
10.1111/j.1525-1594.2004.07381.xsubject
Has Abstractpub_date
2004-10-01 00:00:00pages
927-32issue
10eissn
0160-564Xissn
1525-1594pii
AOR7381journal_volume
28pub_type
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journal_title:Artificial organs
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journal_title:Artificial organs
pub_type: 杂志文章
doi:
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journal_title:Artificial organs
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1994.tb02227.x
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journal_title:Artificial organs
pub_type: 杂志文章
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journal_title:Artificial organs
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doi:10.1111/j.1525-1594.1995.tb02453.x
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pub_type: 杂志文章
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.2009.00924.x
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journal_title:Artificial organs
pub_type: 杂志文章
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1989.tb01579.x
更新日期:1989-12-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2003.00022.x
更新日期:2003-10-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2001.025006486.x
更新日期:2001-06-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2002.06721.x
更新日期:2002-02-01 00:00:00
abstract::We report on 10 patients with acute renal involvement in Hantaan virus infection observed at the Department of Nephrology, Faculty of Medicine, Skopje, Republic of Macedonia, during a period of 3 years (October 1987-July 1990). Eight patients were male and 2 were female, aged 37.5 +/- 4.8 years. The diagnosis of Hanta...
journal_title:Artificial organs
pub_type: 临床试验,杂志文章
doi:10.1111/j.1525-1594.1995.tb02432.x
更新日期:1995-08-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/j.1525-1594.1989.tb02846.x
更新日期:1989-04-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2000.06502-2.x
更新日期:2000-07-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1046/j.1525-1594.2002.06917.x
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journal_title:Artificial organs
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pub_type: 杂志文章
doi:10.1046/j.1525-1594.2002.07087.x
更新日期:2002-10-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
doi:10.1111/aor.12294
更新日期:2014-12-01 00:00:00
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journal_title:Artificial organs
pub_type: 杂志文章
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更新日期:2020-08-01 00:00:00
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pub_type: 杂志文章
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更新日期:2010-09-01 00:00:00
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journal_title:Artificial organs
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pub_type: 杂志文章
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